If you're driving your 70-foot rig at 65 mph in good weather conditions and minimal traffic, you should leave _____ seconds between you and the car ahead of you.

If you're driving your 70-foot rig at 65 mph in good weather conditions and minimal traffic, you should leave _____ seconds between you and the car ahead of you.

• A. 6
• B. 8
• C. 12
• D. 15

Answer: (B)

Large trucks need more following distance than cars because their stopping distance is much longer. At highway speed, you have to account for your perception time, your reaction time, and the braking distance, all of which are greater for a long, heavy rig. The eight-second rule gives you enough cushion to react and brake safely if the vehicle ahead suddenly slows or stops. At 65 mph, that’s about 95 feet per second, so eight seconds amounts to roughly 760 feet of space—a substantial margin for a 70-foot rig. Six seconds would be too close for a truck this size, while twelve or fifteen seconds is more than usually needed in good conditions and can disrupt traffic flow. So eight seconds is the practical, safe following distance for a heavy vehicle at that speed in good weather with light traffic.

Large trucks need more following distance than cars because their stopping distance is much longer. At highway speed, you have to account for your perception time, your reaction time, and the braking distance, all of which are greater for a long, heavy rig. The eight-second rule gives you enough cushion to react and brake safely if the vehicle ahead suddenly slows or stops. At 65 mph, that’s about 95 feet per second, so eight seconds amounts to roughly 760 feet of space—a substantial margin for a 70-foot rig. Six seconds would be too close for a truck this size, while twelve or fifteen seconds is more than usually needed in good conditions and can disrupt traffic flow. So eight seconds is the practical, safe following distance for a heavy vehicle at that speed in good weather with light traffic.